Lapping machine



Nov. 25, 1952 H. s. lNDGE 2, 1

LAPPING MACHINE Filed July 8, 1950 4 Sheets-Sheet 1 Fig.1

[278 22107" f/fEELQAif/Y E @Mwam lizzorrey H. S. lNDGE LAPPING MACHINE Nov. 25, 1952 4 Sheets-Sheet 2 Filed July 8, 1950 Fig. 2

Nov. 25, 1952 H. s. INDGE 2,618,911

LAPPING MACHINE Filed July 8, 1950 4 Sheets-Sheet 3 Fig. 3 n

\23 l2; \Z\ \a free/972807" HERBEBTS. [/YDGE flzzorzzcy UNITED STATES ATENT OFFICE LAPPING MACHINE Herbert S. Indge, Westboro, Mass, assignor to NortonCompany, Worcester, Mass, at corporation'o'f Massachusetts Applieationluly' 8, 1950, .Seri'aLNo. 172341 8 Claims. 1

The-invention relates to lapping machines and more particularly to a machine for automatically' lapping the opposite faces of. relatively large diameter, relatively thin workpieces to a predetermined size and finish.

One object of the invention is to provide a simple and thoroughly practical lapping machine for lapping the opposite plane-faces of relatively large diameter thin workpieces. Another object of the: invention is to provide alapping machine having. two opposed lapping wheels and-a. work cage 'therebetween including a plurality of posi-'' tively driven workholder" members for rotating. the workpieces during a lapping operation. Another object of the invention is to provide awork cage: mechanism comprising a plurality of ring gear workholdershaving central apertures to support the workpieces to be lapped. Another object of the invention is to provide a work cage driving mechanism com-prising. a central driving gear for imparting a simultaneous rotation to a plurality of workholders and to provide idler supports for. maintaining the workholders in driving relationship with the central gear. Other objects will be in part obvious or inpart pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure 'to be' hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. 1. is a vertical sectional view through the lapping machine r Fig. 2 is a vertical sectional view, on an enlarged scale, through the lower lapping wheel, the. Work cage, and the supporting and driving mechanisms therefor;

Fig. 3 is a fragmentary plan view of the lower lapping wheel and the work cage mechanism;

Fig. 4 is a fragmentary elevation, on an enl'arged scale, of the work cage mechanism asshown in Fig. 3;

Fig. 5 is afragmentary plan view of a modified form of the work cage mechanism; and

Fig. 6 is a fragmentary elevation of the work cage mechanism as shown in Fig. 5.

The lappin machine illustrated in the drawings in its general aspects is similar to the lapping, machine disclosed in my prior U. S. Patent No. 2,103,984 dated December 28, 1937. This machine, as illustrated, may comprise a base In which rotatably supports 'a lower lapping wheel H. The base I0 is provided with anupwardl'y extend ing column 12 havingan outwardly extending hollow portion is which rotatabliy supports-a vertical spindle M. The spindle M- .is provided atitslower end with a supporting plate .15 which carries an upper lapping wheel. Hi. The lapping. wheels II and 1-5 are each provided with plane operative-opposed faces for simultaneously lap p ng the opposite sides Of rai (plurality of worlpleces.

Power may be obtainedfrom any suitable source, such as an overhead drive shaft, or an electric motor mounted onor adjacenttothe machine. For the-sake ofillustration,a belt drive' has been shown comprising adriving belt -20 which serves to rotate a pulley 2| which is rotat ably mounted on a horizontally arranged shaft 22'. Theshaft 2 2 is journalled in bearingsiiv, -24,- 25, and 26 which are supported in the base 141-. The inner portion of the pulley 21 is formed as one part of acone clutch. A slidably mounted cone-shaped clutch member 2 1 is keyed on the shaft 22 and serves to cooperate with the clutch face formed within the pulley 21 totransmit powerlfrom' the dllViIlg. belt ill to the shaft 2 21 When the clutch is in the full linepo'sition as shown in Fig. 1-, no power is transmitted to the shaft 22; when: a" is desired to rotate the shaft" 22, the clutch member 21 ismoved toward the right (Fig. 1) into engagement with the-clutchmember within the pulley 21" so as to cause a rotation of the shaft'2'2. Inord'erthat theclu'tch' may be readily operated from the" frontof the: machine; a pivotally mountedcontrol lever 21? is" supported on a stud 29' on the base 18. Thelowei" end of the lever 28 is connected by-a'pin" at with a link 31 which is inturn connected with a slide rod 32 supported in bearings-33 and 34 mounted" onthe base 1B. A yoked memberseismouhtea on the: right-hande'nd. or: the slide rod 32 and engages. a groove as formed in the hub 31- of the clutch member 21. By movementizot the: control lever 28 in a counter clockwise" direction; the clutch member 21 may be thrownintmen gagem'ent with the clutch member within the pulley 2L to cause rotation ofthe shaft-"2'21 A" spring pressed roller 38 cooperating with anar' row point. 39" on the yoked member 35 serves hold the clutch parts eitl-ier into or out of engagement.

The shaftl-Z is providedwith aworm 45 which meshes with a worm gear 46 mountedon the lower end of a vertical shaft 41 The shaft 4 1-- is connected by' a universal joint- 48 with a-- ver-" tical shaft 49. The shaft 49 is preferably a telescopic shaft and is connected by a universal joint 59 with a vertical shaft The shaft 5| is supported in a pair of spaced bearings 52 and 53 carried by an adjustably mounted bracket 54 which is supported on top of the column I2. The shaft 5I is provided with a pulley 55 which is connected by driving belts 56 with a pulley 51 which is keyed on a rotatable sleeve 58. The sleeve 58 is slidably keyed by means of keys 59 to an upwardly extending projection 69 of the spindle I4, so that when the clutch 21 is engaged, the vertical spindle supporting the upper lapping wheel I6 will be rotated.

The bracket 54 is adjustably mounted on the upper surface of the column I2 and is provided with a screw adjustment comprising a screw 62 which is rotatably supported in a bracket 63 fixed to the column I2 and is screw threaded into the bracket 54, so that the bracket 54 may be adjusted transversely of the machine to obtain the desired drive tension on the belts 56.

The lower lapping wheel II is mounted on a V rotatable spider 65 which is keyed to the upper end of a rotatable sleeve 66. The sleeve 66 is journalled in bearings 61 and 68 which are in turn supported within a housing 69 fixedly mounted on the base I9. The lower end of the sleeve 66 supports a worm gear I9 which meshes with a worm II mounted on the shaft 22. It will be readily apparent from the foregoing disclosure that rotary motion of the shaft 22 will be imparted through the driving mechanism above de scribed to impart a rotary motion to the upper lapping wheel I6 and the lower lapping wheel I I to rotate the lapping wheels in opposite directions; 7

A suitable counter-balance mechanism is provided to counter-balance the weight of the upper lapping wheel I6 and its supporting mechanism. This mechanism may comprise a counter-balance weight I5 which is connected by means of a link chain 16 with a sprocket II rotatably supported on a shaft I8. The shaft I8 also supports a second sprocket, not shown, which is connected by a link chain IS with a sprocket 89 mounted on a shaft BI. The shaft 8| supports a small gear 82 which meshes with a rack bar 83 fastened to a vertically movable sleeve 84. The sleeve 84 is provided with bearings 85 and 86 rotatably to support the'vertical spindle I4. This counterbalance mechanism is identical with that shown and fully described in my prior U. S. Patent No. 2,103,984 dated December 28, 1937, to which reference may be had for details of disclosure not contained herein.

In order to limit the downward movement of the upper lapping wheel I6, a suitable stop mechanism is provided positively to limit the downward movement of the lapping wheel so that it bears a definite and predetermined relationship with. the lower lapping wheel and work. This stop mechanism may comprise a stop stud 99 which is carried by a bracket 9| fixedly mounted on a housing 92 which supports the sleeve 84. An adjustable stop screw 93 is carried by a bracket 94 which is adjustably supported on the sleeve 84', a. plurality of threaded holes 95 being provided on the sleeve 84 to facilitate vertically adjusting the bracket 44 relative to the sleeve 84 in setting up the machine for lapping a predetermined workpiece. A micrometer adjusting knob 96 is provided for the adjustably mounted stop 93 to facilitate a precise adjustment of the stop 93 to determine the lowermost position of the upper lapping wheel I6.

A work cage mechanism is provided for simultaneously supporting and lapping a plurality of relatively large diameter relatively thin workpieces 99. This cage mechanism is supported by three vertically extending studs I99, I9I and I92 (Fig. 3) which are supported in bosses I93 and I94 formed integral with a pan I95. Only two of these supporting bosses have been illustrated in Fig. 2. The studs I99, IM and I92 support arcuate shaped plates I96, I91 and I98 respectively. The plate I96 is provided with a stud I99 which supports a rock arm I I9 having a stud III rotatably to support an idler gear I I2. Similarly the plate I96 is provided with a stud II3 which supports a rock arm II4 carrying a stud II5 rotatably to support an idler gear H6. The arcuate shaped plate I9'I is provided with a stud II'I which supports a rock arm I I8 having a. stud II9 rotatably to support an idler gear I29. The plate I9'I also is provided with a stud I2I supporting a rock arm I22 carrying a stud I23 rotatably to support an idler gear I24. The plate I98 is provided with a stud I25 supporting a rock arm I26 having a stud I2'I rotatably to support an idler gear I29. The plate I96 also is provided with a stud I29 supporting a rock arm I39 having a stud I3I rotatably to support an idler gear I32.

A plurality of workholders or cages are provided comprising annular gear-type workholders I35, I36 and I3! provided with central apertures I38, I39 and I49 respectively each being arranged to support a workpiece 99 for a lapping operation. Each of the ring gears or cages I35, I36 and I31 is provided with a work driving stud I4I so that the workpiece supported thereby will be rotated with the cage supporting the same.

A suitable driving mechanism is provided for the work cages I35, I36 and I31 comprising a central driving gear I45 which is fixedly supported on a boss I46. The boss I46 is formed integral with a cup-shaped member I41 which is slidably keyed on an enlarged portion I48 of a central driving shaft I49. The drive shaft I49 is supported at its upper end by an anti-friction bearing I59 and at its lower end by means of a sleeve-type bearing I5 I. A gear I52 is keyed on the lower end of the rotatable sleeve 66. The gear I52 meshes with a gear I53 which is keyed on a rotatable shaft I54. A gear I55 is keyed on the lower end of the shaft I54 and meshes with a gear I56 keyed on the lower end of the shaft I49. It will be readily apparent from the foregoing disclosure that rotary motion of the worm II will be imparted through the gear mechanism just described to rotate the shaft I49 and the driving gear I45 to impart a rotary motionto the workholders I35, I36 and I31. The gears H2, H6, I29, I24, I28 and I32 serve as idler gears which mesh with the work cages which mesh with the gear teeth formed on the peripheries of the workholders or cages I35, I36 and I3! and maintain the holders in driving mesh with the driving gear In order to adjust the idler gears'to maintain them in the proper relationship with the 'work cages, a plurality of arcuate shaped links I69, I6l and I62 are provided to adjustably connect with the rock arm supporting the idlers. The

arcuate shaped link I69 is provided with elon-,

gated slots I63 and I64 located adjacent to its opposite ends.

tively and are screw threaded into the rock arms garage-n.

:3 I14 and. I30" respectively; Similarly the arcuate; shaped link I6I is provided with elongated slots I61 and I68. Clamping screws I69 and I10 pass throughth'e elongated slots I61 and I68 and are screw threaded into the rock arms III] and H8 respectively. Similarly the arcuate shaped link I62 is provided with elongated slots. III and I12.

Clamping screws I13 and I14 pass. through the.

elongated slots. HI and I12 respectively and are screw threaded into the rock arms I22 and I26 respectively. It will be: readily apparent that by adjusting the position of the rock arms to position the idler gears into proper mesh Withthe gear teeth on the peripheries of the work'- holders' or cages I35, I36 and. I31 after which the clamping screws above described are clamped toclamp: the arcuate shaped links I50, I6I and I62 so asfto. hold the rock arms II I, Ill), IIB, I22, I26 and I38 with their. idler gears in the desired meshing engagement with theworkholder or cage gear teeth.

A modified form of support. for the workholders. or cages: I35, I36 and I31 has been illustrated in Figs. 5 and 6. In this construction the vertical rods I58, IEII and I82 serve as a support for an. annular ring I88. The ring I89 serves as a supportfor a plurality of rock arms I8I, I82. which are pivotally supported by means of studs: I83 and I84 carried by the ring I88. The. rock arms. I8I and I82 are provided with studs I85 and I86 respectively which support pivotallyrnounted shoes I81 and I88 respectively. The shoes I81 and I88 are provided with partial cylindrical surfaces I89 and I38 respectively which are shaped to mate with and engage the outer peripheral surfaces of the teeth formed on the workholder I35. The rock arms I8I and I82 are provided with elongated slots I9I and I92 respectively. Clamping screws I93 and I94 pass through the elongated slots I9I and I92 and are screw threaded into the ring I85. It will be readily apparent from the foregoing disclosure that the rock arms I8I and I82 may be swung about their supporting pivots I83 and I88 respectively so as to vary the position of the pivot studs I85 and I86 respectively thereby varying the position of the shoes I81 and I88 respectively. A pair of stop screws I95 and I96 are carried by the ring I86. The stop screws I95 and I96 are each provided with lock nuts and serve to steady and hold the shoes I81 and I88 respectively in predetermined adjusted positions. It will be readily apparent from the foregoing disclosure that by adjustment of the position of the pivot studs I35 and I86 and by adjustment of the stop screws I95 and I96, the shoes I81 and I38 may be readily adjusted into supporting engagement with the workholder I35.

Similar adjustably mounted shoes I810: and I88a are provided for supporting the periphery of the gear teeth on the work cage or holder I35. The supports and adjustments for the shoes IBM and I881: are identical with those described in connection with shoes I81 and I88. These corresponding parts have been identified by the same numerals with the suffix a. A description of the details of these supporting members is not deemed necessary since they operate identical with those previously described. Similarly pivotally mounted adjustable shoes I81b and I882) are provided for engaging the peripheries of gear teeth formed on the work cage or holder I31. The corresponding parts for supporting the shoes I81b and I881) are identical with those described in connection with the shoes I81 and I88: and have: been" designated by the samenumerals with the suffix: b. These parts similarly have not beendescribed' in detail since they are identical with those described in connection with shoes I81 and I88.

The operation of the improved lapping: ma chine will be. readily apparent from the foregoing disclosure. Assuming the parts to have:

been previously adjusted, three workholders I35. I36 and I131 are. placed in operative position in mesh with the. driving gear: H5 and supported either by idler gears as shown in Fig. 3 or" by pairs: of peripherally engaging shoes. as shown in Fig- 5. Workpiec'es 99 to be lapped on opposite flat. faces are then placed one in each workhol'der; The machine is set in motion,. by engagement of the clutch 21,. to: start. the. ra-

tation of the. upper lapping: wheel I6 and the lower lapping wheel II in. opposite. directions. The upper lapping wheel I6 is: then moved downwardlyinto operative "engagement with the upper faces of the workpieces by a hydraulically operated mechanism such as for example that shown. in, my prior U. S. Patent No. 2,103,984 dated December 28, 1937 to which reference may be had for details of disclosure not contained herein. The downward movement of the upper lapping wheel I'6 continues under. pressure un-- til the stop screw 93 engages the stop surface.- 38 during which time the work cages or holders.

I35, I36 and I31 willv be continuously rotated sothat the opposite fiatv faces" of theworkpieces. 86 will be lapped to the. desired andapredetermined extent. After the lapping operation has been completed,v the upper lapping wheel I6 may again be raised to an inoperative position so that the lapped workpieces 99 may be readily removed from the workholders, I35, I36. and I31 after which new workpieces may be inserted therein.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments. may be made. of the above invention and as many changes might be made in the embodiments above set for'th,.it. is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a lapping machine having a base, a pair of opposed axially-aligned lapping wheels supported on said base having opposed plane operative faces, a driving mechanism supported on said base and operatively connected positively to rotate said wheels, and a work cage therebetween for supporting a plurality of relatively large diameter relatively thin flat workpieces comprising a plurality of positively driven ring-type workholders having central work receiving apertures, a central positively rotated driving gear rotatably supported on the base which meshes with all of said workholders, and independently adjustable members supported on said base adjacent to the periphery of the work holders, each of said members having a surface mating with the periphery of a work holder to maintain them in mesh with the central driving gear during a lapping operation.

2. In a lapping machine, as claimed in claim 1, in combination with the parts and features therein specified in which the independent adjustable means includes an annular ring on said base surrounding the lower lapping wheel and having an adjustably mounted shoe pivotally supported on said ring, said shoe having an arouate surface shaped for engaging the periphery of each of the Work holders, and means including an independent adjusting screw on said ring to adjust each of said shoes to maintain the work holders in meshing engagement with the central driving gear during a lapping operation.

- 3. In a lapping machine as claimed in claim 1, in combination with the parts and features thereinspecified of an annular ring surrounding the lower lapping wheel and supported by said base, means including a pair of spaced adjustably mounted shoes supported on the ring, said shoes having an arcuate surface shaped for engagi the periphery of each .of the work holders, and means includingindependent adjusting screws on said ring to adjust each of said shoes to maintain the work holders in meshing engagement with the central driving gear during a lapping operation.

l. In a lapping machine as claimed in claim 1, in combination with the parts and features therein specified an amiular ring surrounding the lower lapping wheel and supported by said base, a pivotally mounted shoe supported by the ring, said shoe having an arcuate surface shaped for engaging the periphery of each of the work holders, and means including an adjusting screw on said ring to adjust the shoe relative to said ring so as to-maintain the Work holders in meshing engagement with a central driving gear dur ing a lapping operation.

5;In a lapping machine as claimed in claim 1,

in combination with the parts and features therein specified an annular ring surrounding the lower lapping wheel and supported by said base, a pair of independent spaced pivotally mounted shoes supported by the ring, said shoes having an arcuate surface shaped for engaging the periphery of each of said work holders, and means including independent adjusting screws on said ring independently to adjust said shoes relative to said ring so as to maintain the work holders in meshing engagement with the central driving gear during a lapping operation.

6. In a lapping machine as claimed in claim 1, in combination with the parts and features therein specified of means including a plurality of, in:- dependent adjustably mounted idler gears supported by the base and positioned inv mesh with said work holders, and means independently to adjust each of said idler gears relative to said base to maintain the work holders in meshing engagement with the central driving gear during a lapping operation.

7. In a lapping machine as claimed in claim 1, in combination with the parts and features therein specified of means including a plurality of pairs of spaced idler gears surrounding the lower lapping wheel and positioned in mesh with each of said work holders at points spaced from the central driving gear, a pivotally mounted arm on saidbase for supporting each of said idler gears, and means to adjust the position of said arms and idler gears to maintain the work holders in meshing engagement with the driving gear during a lapping operation.

8. In a lapping machine as claimed in claim 1, in combination with the parts and features therein specified of means including a plurality of pairs of spaced idler gears, a plurality of pivotally supported arms on said. base surrounding the lower lapping wheel, each of said arms support ing one of said idler gears in mesh with one of the work holders at points spaced from the central driving gear, and means including adjustably mounted links connecting the ends of adjacent arms to facilitate adjusting the position of the idler gears so as to maintain the work holders in meshing engagement with the driving gear during a lapping operation.

HERBERT S. INDGE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STAT-ES PATENTS 

